dfgreene61 Posted June 5, 2014 Report Posted June 5, 2014 My M20J is back from an extended stay at Lasar where it was annualled. During the annual they adjusted the flaps and ailerons. They then went through many iterations of adjusting the rigging on the ailerons and rudder by bending the trailing edges. The plane flies much truer now however I've noticed that in straight and level flight the ailerons are not even with the flaps, they are above the flaps by about an inch or so at the trailing edge. Is this ok or am I paying a drag penalty.
Bennett Posted June 5, 2014 Report Posted June 5, 2014 An inch is quite a bit - more like the reflexing flaps on the Cessna 400 (nee Columbia 400) series, as well as on some LSAs (DOVA DV-1) for example. In high speed cruise flight there is some thought that this keeps laminar flow longer across the wing's cord, hence less drag / more speed. At least that is what Dr. Marden, the aerodynamicist who designed the DOVA, told me. I think that the consensus in the Mooney world is that the ailerons should be at the same height as the flaps, or one or two degrees below. Last December I had LASAR adjust my ailerons to be flush to the flaps, and the aircraft seems "happy" at that setting. I didn't notice any change in TAS from the previous half inch high settings before the adjustments.
John Pleisse Posted June 5, 2014 Report Posted June 5, 2014 Shouldn't be quite an inch...ailerons should have 1 to 2 degrees droop. There really is no "rigging" per se with ailerons. Likely rod end adjustments.
Marauder Posted June 5, 2014 Report Posted June 5, 2014 This is what mine looks like in flight: Sent from my iPad using Tapatalk
Bennett Posted June 5, 2014 Report Posted June 5, 2014 Marauder, Your ailerons (training edge) appear to be flush with the flaps - the same configuration I now have after LASAR spent a good deal of flight time "rigging" mine. No change in TAS that I can discern, but they look "right". N335BB always flew straight, but the ailerons were both about 1/2" higher than the flaps, and I kept reading that they should be flush, or droop 1 to 2 degrees. I had hoped to notice even a small change in TAS, but I never could measure a difference. Of course no two days are exactly alike, but there was nothing noticeable. 1
N201MKTurbo Posted June 5, 2014 Report Posted June 5, 2014 I have found that the higher you rig your ailerons the faster you go. But an inch seems like a lot. So you have to figure are the ailerons to high or are the flaps to low.
dfgreene61 Posted June 5, 2014 Author Report Posted June 5, 2014 I sent Michael at Lasar an email about it. I'll post his response. I don't think I was cruising any different than normal. 150kts true at 10,500/10c/8.5 GPH.
Piloto Posted June 5, 2014 Report Posted June 5, 2014 Rigging the Mooneys does not requires bending the surfaces. For roll there is an adjustment set screw on the flaps outboard hinge for this purpose. The rudder is done by adjusting the actuating link rod length that is easily accesible. The 1" discrepancy you indicate is due to an aileron/flap or rudder divergence. On a properly rig Mooney the flaps should be even with the ailerons and the ball centered at 140kts. With the A/P disconnected there should be no roll tendency to either side with flaps up or flaps down. José
Marauder Posted June 5, 2014 Report Posted June 5, 2014 Marauder, Your ailerons (training edge) appear to be flush with the flaps - the same configuration I now have after LASAR spent a good deal of flight time "rigging" mine. No change in TAS that I can discern, but they look "right". N335BB always flew straight, but the ailerons were both about 1/2" higher than the flaps, and I kept reading that they should be flush, or droop 1 to 2 degrees. I had hoped to notice even a small change in TAS, but I never could measure a difference. Of course no two days are exactly alike, but there was nothing noticeable. Mine are flush but at one time one was up a half inch and the other flush. Turned out to be one of the flaps was drooping a little. The mechanic'a solution was to rigged one aileron up a bit. That was worth a few knots when I had a mechanic with the travel boards rig everything correctly from scratch.
Guest Posted June 5, 2014 Report Posted June 5, 2014 While I may not be as knowledgable as others, it seems to me that rigging the rudder by adjusting the aft rod end will only serve to cause an off set in the pedals. The maintenance manuals for most Mooney models calls for a slight bend of the trailing edge of the aileron (down only) to correct for roll trim issues, this of course is based on the flaps being correctly rigged to the zero degree mark with the correct travel board. Ailerons are rigged from zero to two degrees down. In my experience the amount of droop is related to cruise speed, higher cruise speed requires greater droop to achieve aileron alignment with the flaps in flight. With effort you should be able to achieve hands off ball centred flight at cruise power. Clarence
dfgreene61 Posted June 7, 2014 Author Report Posted June 7, 2014 Response about my ailerons from Mike at LASAR: ----- The ailerons are too high. The ailerons were rigged a couple degrees down when we rigged the ailerons, as per the maintenance manual. There is some internal rigging that can be done to bring the ailerons level, as they tend to rise up in flight. I apologize that it was not noticed prior to delivery. We attempt to simulate air loads in the hanger, but it is not the same as actual air loads. If the aircraft is stable and flying good it is not going to have an adverse effect. ----- I'm too far from LASAR to go back and get it adjusted. No MSC in Utah. Guess I'll live with it until my next annual.
Marauder Posted June 7, 2014 Report Posted June 7, 2014 Response about my ailerons from Mike at LASAR: ----- The ailerons are too high. The ailerons were rigged a couple degrees down when we rigged the ailerons, as per the maintenance manual. There is some internal rigging that can be done to bring the ailerons level, as they tend to rise up in flight. I apologize that it was not noticed prior to delivery. We attempt to simulate air loads in the hanger, but it is not the same as actual air loads. If the aircraft is stable and flying good it is not going to have an adverse effect. ----- I'm too far from LASAR to go back and get it adjusted. No MSC in Utah. Guess I'll live with it until my next annual. Post a picture when you get a chance. I'm curious how high they are. Sent from my iPad using Tapatalk
N201MKTurbo Posted June 7, 2014 Report Posted June 7, 2014 The adjustment is easy. Remove the belly so you have access to the center aileron links. Each aileron push rod is connected to the links with a bolt through the push rod. Remove the access panel at the aileron bell cranks on the wings and loosen the jam nuts on the rod ends. Remove both bolts at the links and rotate the push rods the same number of 1/2 turns until the ailerons are where you want them. Put the plane back together.
Guest Posted June 7, 2014 Report Posted June 7, 2014 I'd love to tell you it's difficult, however any reasonably competent maintainer with a brain, a manual and some tools should be able to do the job. But please do follow the procedure as laid out in the manual. Clarence
jetdriven Posted June 8, 2014 Report Posted June 8, 2014 The service manual has you adjust the ailerons at the bellcrank in the wing forward of the aileron. This is rigging, and it's critical. Please follow the service manual as Clarence said.
captainglen Posted May 7, 2016 Report Posted May 7, 2016 The service manual has you rig the ailerons with a rig bar then it tells you to rig the flaps to be even with the ailerons. My ailerons are about 1/2" below my flaps which means the flap stops are miss rigged. I may rig them lower but I have heard some good things about pre scheduling the flaps. I will try some runs with them up and pre scheduled and some runs with them pumped down to even to see if there is any discernable difference. If there is none I will adjust the flaps.
Guest Posted May 7, 2016 Report Posted May 7, 2016 6 hours ago, captainglen said: The service manual has you rig the ailerons with a rig bar then it tells you to rig the flaps to be even with the ailerons. My ailerons are about 1/2" below my flaps which means the flap stops are miss rigged. I may rig them lower but I have heard some good things about pre scheduling the flaps. I will try some runs with them up and pre scheduled and some runs with them pumped down to even to see if there is any discernable difference. If there is none I will adjust the flaps. You will need someone with the correct travel boards and the correct maintenance manual before attempting to rig flight controls. Clarence
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